You Can Grow It: Harvesting hops

On this segment of "You Can Grow It," our master gardener Jim Duthie takes a visit to a hop farm.

Author:
Jim Duthie

Published:
4:59 PM MDT September 14, 2017

Updated:
6:00 PM MDT October 26, 2017

Have you ever wondered what those unusual looking vines are growing on some Canyon County farms? They’re probably hops, which supply a growing industry of microbreweries here in Idaho.

Garden master Jim Duthie takes us on a tour of a hops processing plant, and shows us how these unusual plants are grown and harvested, and why they thrive here in southwest Idaho.

You’ve probably driven past them and wondered what these strange vines are. These are hops, and hops is a big industry in southwest Idaho.

Hops fields are a unique and interesting sight in Idaho’s farm country, with long, straight corridors between high walls of leafy, aromatic vines.

Hops are the flowers of the hop plant, and are used primarily as a flavoring and stability agent in beer.

The hops plants are perennial, which means that they grow back each spring. The fields remain planted for five to eight years, depending on the need for that particular hop variety in the marketplace.

As the shoots emerge, they’re trained to grow up strings to an overhead trellis. The vines, better known as bines, can grow to be well over twenty feet tall.

The plants produce 1- to 2-inch long flowers that resemble small pine cones. Each of the scales, or petals, of the flower produces a yellow powder that contains the acids and oils that give the hops their character and flavor.

So why are there so many hop farms in Southwest Idaho? It has a lot to do with being halfway between the equator and the North Pole.

“The reason hops thrive here…hops are a daylight sensitive crop. They need to be close to the 45th latitude,” said Brock Obendorf of Obendorf Farms.

“The lower you get there’s too much day length and the hops will not flower. So you need to have the right day length to flower.”

The climate here also plays an important role in growing hops.

“And they’ve got to have a certain amount of freeze nights in the wintertime to be able to reactivate in the spring. So this area allows for that.”

“And this area, too, is…the storms aren’t as bad, like in the Midwest on that latitude, and the climate, with the temperature and the seasons, work well for that.”

The main hops growing area here in Southwest Idaho is in Canyon County, particularly around Parma, Notus, Wilder and Greenleaf. But neighboring states actually have a larger hop industry.

Hop growing in Idaho began in 1934 when some Canyon County farmers first installed trellises and started growing the first plants. Brock’s grandfather, Ray, started growing hops in 1948.

“Our hops are all over the world. They go to brokers, and then they’re distributed everywhere.”

So how do the hops get from the fields to the breweries, who use them to make beer?

Late summer is harvest time for hops. The vines are pulled down and transported on these trucks to the separation shed where the hop flowers are removed.

The vines are hung upside-down on conveyors that take them to the strippers, to separate the hops from the vines and leaves. They’re hung upside-down because the hop flowers are more numerous at the tops of the vines. The flowers go through a series of steps to clean the hops, removing any unwanted plant material and other debris. Then the discarded leaves and vines are chopped up and set aside to be used for cattle feed.

Next, the hops are transported by conveyor to a drying facility. They come in with a moisture content of about 75 percent. They’re dumped into huge drying vats about three to four feet deep, and each drying vat holds about two acres’ worth of hops.

Warm air, at about 135 degrees, is forced up through the floor of the vat, where the hops are dried to about 9.5 percent moisture content, a process that takes about eight to ten hours.

“What does it smell like? Smells like an IPA. Yeah, smells great. Exactly.”

From here, the dried hops are taken to the packing shed where a slot in the floor pushes air up through the pile of dried hops to cool them back down. They’re then scooped into a machine that compresses them into 200-pound bales, which are wrapped and ready for shipping.

And who buys these Idaho-grown hops?

“A lot of microbrewing, a lot of big breweries.”

Including a growing microbrewery industry here in Idaho, as well as throughout the world.

There are four main varieties of hops grown in southern Idaho – Galena, nugget, Chinook and Zeus. Each one has been developed for the distinctive flavors they give to beer.

Hops are also used in herbal medicine as a treatment for anxiety and insomnia. A pillow filled with hops is supposed to be a remedy for sleeplessness. And hops can also be eaten. The young shoots of the vines are edible and can be cooked similar to asparagus.